Problem: Simplify the following expression: $n = \dfrac{2a - 12}{4a - 6} + \dfrac{-9a + 18}{4a - 6}$
Solution: Since the expressions have the same denominator we simply combine the numerators: $n = \dfrac{2a - 12 - 9a + 18}{4a - 6}$ Combine like terms: $n = \dfrac{-7a + 6}{4a - 6}$